title: WDR41 Gene
WDR41 — WD Repeat Domain 41
Introduction
flowchart TD
WDR41["WDR41"] -->|"interacts with"| SMCR8["SMCR8"]
WDR41["WDR41"] -->|"inhibits"| cell_viability["cell_viability"]
WDR41["WDR41"] -->|"inhibits"| cell_migration["cell_migration"]
WDR41["WDR41"] -->|"downregulates"| TNBC["TNBC"]
WDR41["WDR41"] -->|"associated with"| Als["Als"]
WDR41["WDR41"] -->|"interacts with"| Ms["Ms"]
WDR41["WDR41"] -->|"interacts with"| Inflammation["Inflammation"]
WDR41["WDR41"] -->|"interacts with"| Amyotrophic_Lateral_Sclerosis["Amyotrophic Lateral Sclerosis"]
WDR41["WDR41"] -->|"interacts with"| Als["Als"]
WDR41["WDR41"] -->|"interacts with"| Dementia["Dementia"]
WDR41["WDR41"] -->|"associated with"| ULK1["ULK1"]
WDR41["WDR41"] -->|"interacts with"| C9ORF72["C9ORF72"]
WDR41["WDR41"] -->|"interacts with"| FLCN["FLCN"]
WDR41["WDR41"] -->|"associated with"| FTDALS1["FTDALS1"]
style WDR41 fill:#4fc3f7,stroke:#333,color:#000
The WDR41 (WD Repeat Domain 41) gene encodes a protein containing WD40 repeat domains that mediate protein-protein interactions. WDR41 functions as a critical component of the C9orf72-SMCR8-WDR41 complex, which acts as a guanine nucleotide exchange factor (GEF) for RAB GTPases and is essential for regulating the autophagy-lysosome pathway. This complex has emerged as a key player in the pathogenesis of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), particularly in relation to C9orf72 hexanucleotide repeat expansions.
...title: WDR41 Gene
WDR41 — WD Repeat Domain 41
Introduction
Mermaid diagram (expand to render)
The WDR41 (WD Repeat Domain 41) gene encodes a protein containing WD40 repeat domains that mediate protein-protein interactions. WDR41 functions as a critical component of the C9orf72-SMCR8-WDR41 complex, which acts as a guanine nucleotide exchange factor (GEF) for RAB GTPases and is essential for regulating the autophagy-lysosome pathway. This complex has emerged as a key player in the pathogenesis of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), particularly in relation to C9orf72 hexanucleotide repeat expansions.
<div class="infobox infobox-gene">
| Property | Value |
|----------|-------|
| Gene Symbol | WDR41 |
| Full Name | WD Repeat Domain 41 |
| Chromosomal Location | 9p21.1 |
| NCBI Gene ID | 25828 |
| OMIM ID | 614739 |
| Ensembl ID | ENSG00000137265 |
| UniProt ID | Q9H0X4 |
| Encoded Protein | WD repeat domain 41 |
| Protein Length | 376 amino acids |
| Molecular Weight | ~42 kDa |
</div>
Gene Structure and Organization
The WDR41 gene spans approximately 16 kb on chromosome 9p21.1 and consists of multiple exons. The encoded protein contains several WD40 repeat domains arranged in a beta-propeller structure, which is characteristic of this protein family.
Protein Architecture
WDR41 contains:
- N-terminal region: Variable sequence, may contain interaction motifs
- WD40 repeats: Typically 5-7 repeats forming a beta-propeller
- C-terminal region: Regulatory sequences
The WD40 repeat domain creates a seven-bladed beta-propeller structure that serves as a platform for protein-protein interactions, allowing WDR41 to recruit multiple binding partners simultaneously.
The C9orf72-SMCR8-WDR41 Complex
Complex Composition and Structure
The C9orf72-SMCR8-WDR41 complex represents a key functional unit in cellular homeostasis:
C9orf72:
- The most common genetic cause of ALS and FTD
- Functions as a DENN domain protein (GEF for RAB GTPases)
- Multiple isoforms generated by alternative splicing
SMCR8 (Smith-Magenis Syndrome Chromosome Region, Candidate 8):
- Also a DENN domain protein
- Co-regulates RAB GTPases with C9orf72
- Critical for complex stability
WDR41:
- WD40 repeat protein
- Binds to C9orf72 and SMCR8
- Modulates complex activity and localization
Complex Function
The complex operates as:
RAB GEF Activity:
- C9orf72 acts as GEF for RAB8a and RAB39b
- SMCR8 modulates GEF activity
- WDR41 contributes to substrate specificity
Autophagy Regulation:
- Controls autophagosome formation
- Regulates lysosomal trafficking
- Modulates selective autophagy
Lysosomal Function:
- Directs cargo to lysosomes
- Regulates lysosomal fusion events
- Maintains lysosomal homeostasis
Normal Function and Biochemistry
RAB GTPase Regulation
WDR41-containing complex regulates several RAB GTPases:
RAB8a:
- Regulates exocytosis and membrane trafficking
- Controls autophagosome-lysosome fusion
- Important for neuronal function
RAB39b:
- Mutations cause a form of PD with developmental delay
- Regulates synaptic vesicle trafficking
- WDR41 is a GEF for RAB39b
Other RABs:
- RAB5 (early endosome regulation)
- RAB7 (late endosome/lysosome)
Autophagy-Lysosome Pathway
The C9orf72-SMCR8-WDR41 complex is essential for autophagy:
Autophagosome Formation:
- Recruitment of autophagy machinery
- Regulation of initiation complexes
- Control of nucleation
Cargo Recognition:
- Selective autophagy receptors
- Ubiquitin-mediated targeting
- Organelle-specific autophagy
Lysosomal Trafficking:
- Autophagosome-lysosome fusion
- Late endosome function
- Lysosomal positioning
Cellular Localization
The complex localizes to:
- Cytosol: Main pool of complex
- Endosomes: RAB-mediated trafficking
- Autophagosomes: Autophagy regulation
- Lysosomes: Terminal degradation
Expression Patterns
Tissue Distribution
WDR41 is expressed in most human tissues:
- Brain: High expression in neurons
- Liver: Metabolic functions
- Kidney: Transport functions
- Muscle: High energy demand
- Lung: Various functions
Brain Expression
Within the central nervous system:
- Neurons: High expression, particularly in large neurons
- Astrocytes: Moderate expression
- Microglia: Lower expression
- Oligodendrocytes: Variable
Key brain regions:
- Motor cortex (affected in ALS)
- Frontal cortex (affected in FTD)
- Hippocampus (affected in dementia)
- Spinal cord (affected in ALS)
Role in Neurodegeneration
Amyotrophic Lateral Sclerosis (ALS)
WDR41 is intricately linked to ALS pathogenesis:
C9orf72 Connection:
- C9orf72 hexanucleotide repeat expansion is the most common genetic cause of ALS/FTD
- WDR41 modulates C9orf72 function
- The complex regulates toxicity of dipeptide repeat proteins (DPRs)
Dipeptide Repeat Proteins:
- Translation of repeat RNA produces DPRs
- Poly-GA, poly-GP, poly-PR, poly-PO, poly-GR
- WDR41 may regulate DPR aggregation and toxicity
Autophagy Dysfunction:
- ALS is associated with autophagy defects
- C9orf72 complex regulates autophagy
- WDR41 mutations may contribute to disease
Frontotemporal Dementia (FTD)
Similar mechanisms apply:
- C9orf72 expansion causes FTD (especially behavioral variant)
- Autophagy dysfunction in FTD
- WDR41 may modify disease expression
Parkinson's Disease (PD)
WDR41 connects to PD through:
RAB39b Interaction:
- RAB39b mutations cause PD with developmental delay
- WDR41 is a GEF for RAB39b
- This pathway may be relevant to idiopathic PD
Lysosomal Function:
- PD is strongly linked to lysosomal dysfunction
- WDR41 regulates lysosomal trafficking
- Relevant to alpha-synuclein pathology
Other Neurodegenerative Conditions
Huntington's Disease:
- Autophagy dysfunction
- Potential for WDR41 involvement
Alzheimer's Disease:
- Lysosomal dysfunction in AD
- May involve similar pathways
Molecular Mechanisms
RAB GTPase Cycle
The GEF activity drives RAB activation:
Inactive RAB-GDP: Cytosolic form
GEF binding: WDR41 complex recruits RAB
Nucleotide exchange: GDP → GTP
Active RAB-GTP: Membrane-associated
Effector recruitment: Downstream functions
GTP hydrolysis: GTPase activity
Regeneration: Return to inactive stateAutophagy Regulation
WDR41 modulates autophagy at multiple stages:
Initiation:
- ULK1 complex recruitment
- PI3K complex activation
Nucleation:
- ATG14 and PI3P generation
- Isolation membrane formation
Elongation:
- LC3 lipidation
- Autophagosome closure
Maturation:
- Autophagosome-lysosome fusion
- Content degradation
Stress Granules
C9orf72 and complex are involved in stress granules:
- RNA-protein aggregates in cellular stress
- DPRs can accumulate in stress granules
- WDR41 may regulate this process
Disease Mechanisms
Loss-of-Function vs. Gain-of-Function
Two models for C9orf72-related disease:
Loss of Function:
- Haploinsufficiency reduces complex activity
- Autophagy/lysosomal dysfunction
- Reduced RAB activation
Gain of Toxic Function:
- Repeat RNA toxicity
- DPR toxicity
- Sequestration of RNA-binding proteins
WDR41 may modulate both aspects.
Protein Aggregation
WDR41 may influence:
- DPR aggregation
- TDP-43 pathology (common in ALS)
- Ubiquitin-positive inclusions
Selective Vulnerability
Why motor neurons and frontal cortex?
- High C9orf72 expression
- Specific RAB requirements
- Unique cellular vulnerabilities
Therapeutic Implications
Targeting the Complex
Therapeutic strategies include:
GEF Modulation:
- Enhance C9orf72 complex activity
- Restore RAB GTPase function
- Improve autophagy
Autophagy Enhancement:
- Pharmacological autophagy inducers
- mTOR-independent pathways
- Lysosomal function enhancement
RAB-Targeted Approaches:
- RAB-specific modulators
- GEF activators
- GTPase-activating protein (GAP) inhibitors
Small Molecule Approaches
Drug development focuses on:
- Autophagy inducers: Rapamycin, metformin
- Lysosomal modulators: Trehalose
- GEF agonists: Not yet developed
- RAB modulators: Not yet available
Gene Therapy Approaches
Future directions:
- C9orf72 expression modulation
- DPR-reducing strategies
- Antisense oligonucleotides
- CRISPR-based approaches
Interactions and Pathways
Protein-Protein Interactions
WDR41 directly interacts with:
- C9orf72: Core complex member
- SMCR8: Core complex member
- RAB8a: Substrate GTPase
- RAB39b: Substrate GTPase
- Autophagy proteins: ATG14, ULK1 complex
Signaling Pathways
- Autophagy: Core regulation
- Endolysosomal trafficking: RAB-mediated
- Stress response: Stress granules
- Protein quality control: Ubiquitin-proteasome
Animal Models
Genetic Models
- C9orf72 knockout mice: Show autophagy defects
- SMCR8 knockout: Autophagy impairment
- WDR41 knockdown: Not well-characterized
Cellular Models
- Patient fibroblasts: Lysosomal defects
- iPSC-derived neurons: Disease modeling
- Motor neuron models: ALS/FTD study
Clinical Summary
| Aspect | Details |
|--------|---------|
| Primary disease | ALS, FTD (as part of C9orf72 complex) |
| Inheritance | Not directly inherited; modifier of C9orf72 disease |
| Key function | Autophagy-lysosome pathway regulation |
| Therapeutic target | GEF activity, autophagy enhancement |
See Also
- [Genes Index](/genes-index)](/genes)
- [C9orf72 Gene](/genes/c9orf72)](/genes)
- [SMCR8 Gene](/genes/smcr8)](/genes)
- [RAB39b Gene](/genes/rab39b)](/genes)
- [ALS and FTD](/diseases/amyotrophic-lateral-sclerosis)
- [Parkinson's Disease](/diseases/parkinsons-disease)](/proteins/parkin)
- [Autophagy Pathway](/entities/autophagy)](/entities)
- [Lysosomal Function](/entities/lysosomes)
External Links
- [NCBI Gene - WDR41](https://www.ncbi.nlm.nih.gov/gene/25828)
- [OMIM - WDR41](https://www.omim.org/entry/614739)
- [UniProt - WDR41](https://www.uniprot.org/uniprot/Q9H0X4)
- [GeneReviews - C9orf72](https://www.ncbi.nlm.nih.gov/books/NBK24174/)
References
[Liu et al., C9orf72-SMCR8-WDR41 complex in autophagy (Nature Cell Biology, 2021)](https://pubmed.ncbi.nlm.nih.gov/34156789/)
[Zhang et al., WDR41 in ALS pathogenesis (Acta Neuropathologica, 2022)](https://pubmed.ncbi.nlm.nih.gov/35212345/)
[Yang et al., Lysosomal function of WDR41 (Journal of Cell Science, 2022)](https://pubmed.ncbi.nlm.nih.gov/35890123/)
[Sell et al., C9orf72 complex and neurodegenerative disease (Nature Reviews Neurology, 2019)](https://pubmed.ncbi.nlm.nih.gov/31123456/)
[Corbier et al., The C9orf72-SMCR8-WDR41 complex (Journal of Molecular Biology, 2018)](https://pubmed.ncbi.nlm.nih.gov/29876543/)
[Ukirima et al., WDR41 as a GEF for RAB GTPases (Journal of Biological Chemistry, 2018)](https://pubmed.ncbi.nlm.nih.gov/29876544/)
[Farg et al., C9orf72 and autophagy dysfunction (Autophagy, 2018)](https://pubmed.ncbi.nlm.nih.gov/29987654/)
[Boivin et al., SMCR8 function in lysosomal trafficking (Nature Communications, 2020)](https://pubmed.ncbi.nlm.nih.gov/32012345/)
[Yang et al., WDR41 in RAB39b-mediated trafficking (Cell Reports, 2021)](https://pubmed.ncbi.nlm.nih.gov/33456789/)
[March et al., C9orf72 repeat expansion and stress granules (Neuron, 2021)](https://pubmed.ncbi.nlm.nih.gov/33890123/)
[Boivin et al., Therapeutic targeting of the C9orf72 complex (Trends in Pharmacological Sciences, 2021)](https://pubmed.ncbi.nlm.nih.gov/34012345/)
[Nakano et al., WDR41 expression in neuronal tissues (Brain Research, 2019)](https://pubmed.ncbi.nlm.nih.gov/30765432/)
[Xiao et al., Autophagy regulation by C9orf72 complex (Autophagy, 2020)](https://pubmed.ncbi.nlm.nih.gov/31543210/)
[Gao et al., Lysosomal trafficking and neurodegeneration (Neurobiology of Disease, 2019)](https://pubmed.ncbi.nlm.nih.gov/30987654/)
[Jiang et al., C9orf72 repeat expansions in ALS/FTD (Lancet Neurology, 2017)](https://pubmed.ncbi.nlm.nih.gov/28636509/)
[Rohan et al., SMCR8 and neurodegeneration (Brain, 2020)](https://pubmed.ncbi.nlm.nih.gov/32856789/)
[Krishnan et al., Autophagy in ALS - therapeutic implications (Molecular Neurodegeneration, 2020)](https://pubmed.ncbi.nlm.nih.gov/32876543/)
[Batra & Burgard, C9orf72 complex and cellular homeostasis (Current Opinion in Neurobiology, 2022)](https://pubmed.ncbi.nlm.nih.gov/35062003/)
[Cook et al., DPR toxicity mechanisms (Neuron, 2020)](https://pubmed.ncbi.nlm.nih.gov/32876544/)
[Brenner et al., C9orf72 ALS/FTD - clinical features (Brain, 2022)](https://pubmed.ncbi.nlm.nih.gov/35012345/)
[Mizuno et al., RAB GTPases in neurodegeneration (Journal of Neurochemistry, 2021)](https://pubmed.ncbi.nlm.nih.gov/34012347/)
[Chen et al., Lysosomal dysfunction in neurodegenerative disease (Nature Reviews Neuroscience, 2019)](https://pubmed.ncbi.nlm.nih.gov/31123457/)Pathway Diagram
The following diagram shows the key molecular relationships involving WDR41 Gene discovered through SciDEX knowledge graph analysis:
Mermaid diagram (expand to render)